Various devices can be placed in a well traversing a hydrocarbon bearing subterranean formation. Fluids in the wellbore can have properties such as high electrical conductivity that can negatively affect the devices placed downhole in the well. In some applications, the wellbore fluids can encumber transmission of signals utilized by the downhole devices. In other applications, the wellbore fluids allow transmission of signals that can interfere with the operation of downhole devices. These and other effects of wellbore fluid can reduce efficiency and accuracy of downhole devices.